U.S. patent number 11,108,252 [Application Number 16/556,398] was granted by the patent office on 2021-08-31 for charging sequence control of a power electronics system.
This patent grant is currently assigned to Dr. Ing. h.c. F. Porsche Aktiengesellschaft. The grantee listed for this patent is Dr. Ing. h.c. F. Porsche Aktiengesellschaft. Invention is credited to Raoul Heyne, Timo Kaul.
United States Patent |
11,108,252 |
Heyne , et al. |
August 31, 2021 |
Charging sequence control of a power electronics system
Abstract
A method for charging sequence control of a power electronics
system, in which a charging power is provided by the power
electronics system, in which a charging unit, which is operated by
a user and which transfers the charging power to a battery, is
controlled by a charging control system. A communication exchange
is carried out at least between a control device of the power
electronics system and the charging control system, in which a
plurality of charging process states are predetermined, in which
sequences between the charging process states are stored in a
program sequence plan and in which the program sequence plan is
used for charging sequence control of the power electronics system.
For the event of a fault the charging process states "Not ready to
charge" and "Fault in charging process" are predetermined.
Inventors: |
Heyne; Raoul (Wiernsheim,
DE), Kaul; Timo (Bietigheim-Bissingen,
DE) |
Applicant: |
Name |
City |
State |
Country |
Type |
Dr. Ing. h.c. F. Porsche Aktiengesellschaft |
Stuttgart |
N/A |
DE |
|
|
Assignee: |
Dr. Ing. h.c. F. Porsche
Aktiengesellschaft (N/A)
|
Family
ID: |
1000005777857 |
Appl.
No.: |
16/556,398 |
Filed: |
August 30, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20200076210 A1 |
Mar 5, 2020 |
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Foreign Application Priority Data
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Sep 3, 2018 [DE] |
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102018121404.9 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60L
53/305 (20190201); H02J 7/0042 (20130101); B60L
53/18 (20190201); G07F 15/005 (20130101); H02J
7/0013 (20130101) |
Current International
Class: |
H02J
7/00 (20060101); B60L 53/18 (20190101); B60L
53/30 (20190101); G07F 15/00 (20060101) |
Field of
Search: |
;320/107 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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102009036816 |
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Feb 2011 |
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DE |
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102012204675 |
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Dec 2012 |
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DE |
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102011113355 |
|
Mar 2013 |
|
DE |
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102017124054 |
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Apr 2018 |
|
DE |
|
Primary Examiner: Parihar; Suchin
Attorney, Agent or Firm: RatnerPrestia
Claims
What is claimed is:
1. A method for charging sequence control of a power electronics
system, in which a charging power is provided by the power
electronics system, the method comprising: controlling a charging
unit, which is operated by a user and which transfers the charging
power to a battery, using a charging control system, carrying out a
communication exchange at least between a control device of the
power electronics system and the charging control system, in which
a plurality of charging process states are predetermined, in which
sequences between the charging process states are stored in a
program sequence plan, and in which the program sequence plan is
used for charging sequence control of the power electronics system,
proceeding from a switch-on process, predetermining the charging
process states "Initialization," "Ready to charge," "Initialization
of charging interface," "Insulation measurement," "Precharging,"
"Charging," "End charging process," "Charging process terminated,"
and for the event of a fault the charging process states "Not ready
to charge" and "Fault in charging process," wherein the respective
charging process state is supplied with at least one respective
task and/or is formed by at least one respective piece of state
information coupled to the respective charging process state,
forming the communication exchange with the charging control system
by at least one of the pieces of state information, wherein, if no
fault arises, a change is made to a respective next charging
process state as soon as a respective task is ended and/or a change
is triggered by communication exchange with the charging control
system, and wherein, if a fault arises, a change is made to the
charging process states "Fault in the charging process" or "Not
ready to charge" and a change is made to the charging process state
"Ready to charge" after the fault has been eliminated.
2. The method as claimed in claim 1, in which the control device of
the power electronics system is formed by a power electronics
control device.
3. The method as claimed in claim 1, in which the control device of
the power electronics system is formed by a ChargeBox
controller.
4. The method as claimed in claim 1, in which the power electronics
system, including control device, and the charging control system
are arranged in a physically separated manner.
5. The method as claimed in claim 1, in which the communication
exchange is performed by Ethernet and/or powerline communication
and/or WLAN and/or LAN and/or CAN bus and/or mobile radio.
6. The method as claimed in claim 1, further comprising performing
a rapid charging process, a high charging power of which is
provided either by a high direct-voltage or a high direct
current.
7. A system for charging sequence control of the power electronics
system, comprising: the power electronics system, the control
device for the power electronics system and the charging unit,
which comprises the charging control system, wherein the system is
configured, in order to charge the battery of an electric vehicle,
to carry out the method as claimed in claim 1 by way of charging
sequence control on the respective control device for the power
electronics system and the charging control system.
8. The system as claimed in claim 7, in which the control device
for the power electronics system is a power electronics control
device.
9. The system as claimed in claim 7, in which the control device
for the power electronics system is a ChargeBox controller.
10. The system as claimed in claim 7, further comprising a
CoolingBox, a charging plug on the charging station, a charging
plug control device and an electric vehicle fitted with the
battery.
11. The method as claimed in claim 1, wherein if the fault arises
during the "Initialization" state, the change is made to the
charging process state "Not ready to charge".
12. The method as claimed in claim 1, when the change is made to
the charging process state "Fault in the charging process," a
change is made to the charging process state "Not ready to charge"
if the fault cannot be eliminated within predetermined parameters,
and a change is made to the charging process state "Ready to
charge" only after a readiness to charge has been re-established.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority to German Patent Application No.
10 2018 121 404.9, filed Sep. 3, 2018, the content of such
application being incorporated by reference herein in its
entirety.
FIELD OF THE INVENTION
The present invention relates to a method for charging sequence
control of a power electronics system, which method relates to
charging electric vehicles in a charging park. A system, which
contains the charging sequence controller of the power electronics
system, is also claimed.
BACKGROUND OF THE INVENTION
Charging parks are provided for charging or rapidly charging an
electric vehicle using high direct-current voltages or direct
currents. Said charging parks may have a plurality of charging
units, for example charging columns or charging stations, and
comprise a plurality of components such as, for example, a cooling
unit, also referred to as a CoolingBox, and/or a power electronics
system effecting the high direct-current voltages or direct
currents, designed either as a standalone module--also referred to
as an LEM--with a power electronics control device, or integrated
into what is known as a ChargeBox--also referred to as a CBX--with
a ChargeBox controller as control device. With most charging parks
installed today, it must be assumed that the various components are
restricted to the charging columns or charging stations. Although
the components can be managed by a single main control device owing
to said physical unit within a respective charging column,
communication of a plurality of components present in a charging
station is also conceivable. The latter is described in document DE
10 2011 113 355 A1, which is incorporated by reference herein, in
which state information of the components of the charging station
is exchanged with a central computer.
In contrast, if the components are physically distributed,
communication between the respective components or the control
devices thereof is essential. In this case, it may also be
necessary to conduct communication between a respective charging
station and a central management system for example with respect to
a charging power to be provided. In this respect, document DE 10
2009 036 816 A1, which is incorporated by reference herein,
discloses a method and an apparatus for controlling charging
stations for electric vehicles, which is intended to minimize peak
load demands by a plurality of electric vehicles charging at the
same time. To this end, a plurality of charging stations are
preferably combined to form a group and a charging power to be
respectively yielded per group is estimated by communication with
the respective groups by means of a central computer.
The charging stations in use worldwide are now provided with
different components that communicate with one another, wherein the
communication must be coordinated accordingly. Furthermore, the
components must implement the charging sequences in a manner
outwardly conforming to standards. To this end, industrial
standards DIN EN 61851 and DIN SPEC 70121 describe the charging
sequence at a level of powerline communication, also referred to by
PLC, in a manner quite accurate in detail. However, it is
conceivable to stipulate simpler communication between the
individual components.
SUMMARY OF THE INVENTION
Described herein is a method, which ensures simple communication in
the case of physically distributed components, in particular with a
power electronics system located outside of the charging unit. To
this end, meaningful states should be developed, which make
possible a clear and reliable transition through a charging
sequence. Programming effort for charging sequence control in this
regard should in this case be designed as simply as possible so
that the charging sequence results in a simple sequence protocol
containing all the essential features. Furthermore, the charging
sequence should take into account all the various charging
standards. Also described herein is a correspondingly designed
power electronics system.
A method for charging sequence control of a power electronics
system is proposed, in which a charging power is provided by the
power electronics system, in which a charging unit, which is
operated by a user and which transfers the charging power to a
battery, is controlled by a charging control system or a charging
control device, in which a communication exchange is carried out at
least between a control device of the power electronics system and
the charging control system, in which a plurality of charging
process states are predetermined, in which sequences between the
charging process states are stored in a program sequence plan and
in which the program sequence plan is used for charging sequence
control of the power electronics system, wherein, proceeding from a
switch-on process, the charging process states "Initialization",
"Ready to charge", "Initialization of charging interface",
"Insulation measurement", "Precharging", "Charging", "End charging
process", "Charging process terminated", and for the event of a
fault the charging process states "Not ready to charge" and "Fault
in charging process" are predetermined, wherein the respective
charging process state is supplied with or coupled to at least one
respective task and/or is formed by at least one respective piece
of state information, wherein the communication exchange with the
charging control system is formed by at least one of the pieces of
state information, wherein, if no fault arises, a change is made to
a respective next charging process state, possibly after a time
delay, as soon as a respective task is ended and/or a change is
triggered by communication exchange with the charging control
system, and wherein, if a fault arises, a change is made to the
charging process states "Fault in the charging process" or "Not
ready to charge" and a change is made to the charging process state
"Ready to charge" after the fault has been eliminated.
In one embodiment of the method according to aspects of the
invention, the control device of the power electronics system is
formed by a power electronics control device. The power electronics
system including power electronics control device may form within a
charging park a separate module, which is referred to as LEM by a
person skilled in the art.
In another embodiment of the method according to aspects of the
invention, the control device of the power electronics system is
formed by a ChargeBox controller. In this case, for providing the
charging power, a ChargeBox has inter alia the power electronics
system and, as control device, the ChargeBox controller.
In one embodiment of the method according to aspects of the
invention, the power electronics system, including control device,
and the charging control system are arranged in a physically
separated manner. If necessary, the power electronics system, in
which heat develops during operation, is supplied with a cooling
unit and arranged at an appropriate distance from the charging unit
in which the charging control system is installed in order to not
negatively impact a user of the charging unit by the noisy cooling
unit.
In the context of the present disclosure, communication exchange
means transmission of respective messages or signals between the
power electronics system or the control device of the power
electronics system and a further component and/or a control device
of the charging park or electric vehicle, in particular the
charging control system or the charging control device.
In yet another embodiment of the method according to aspects of the
invention, the communication exchange is performed by means of
Ethernet and/or powerline communication and/or WLAN and/or LAN
and/or CAN bus and/or mobile radio. Said communication means are
intended to illustrate only an exemplary selection and do not
restrict other possible forms of the communication exchange. For
example, it is conceivable that the communication exchange between
the charging control system and the power electronics system takes
place via a fixedly installed transmission cable, for example
Ethernet within a LAN, but communication with an electric vehicle
to be charged is done via mobile radio.
In the following text, a possible program sequence plan of charging
sequence control on a control device of the power electronics
system is described. The control device of the power electronics
system carries out communication exchange at least with the
charging control system. By way of example, the power electronics
control device is used as the control device of the power
electronics system; the program sequence plan is thus described on
the basis of a power electronics module, referred tows LEM as
mentioned above. In the same way, the program sequence plan is also
conceivable with the ChargeBox controller of a ChargeBox instead of
the power electronics control device of an LEM. The transition
through the charging process states is effected in such a way that
the respective charging process state is supplied with or coupled
to at least one task, for example to the task of initialization,
and/or forms a piece of state information, for example "I
(respective addressed component) am ready to charge" or, with
respect to the above task, "I (respective addressed component) have
finished initialization". If the state information has been formed,
communication exchange with the charging control system takes place
thereby. Except in the case of a fault arising or in the case of
the charging process being interrupted, for example by the user of
the charging unit, a change is only made to the next charging
process state provided in the program sequence plan when this is
demanded by the charging control system through communication
exchange with the charging control system.
The program sequence plan begins in a switched-off state of the LEM
and is passed through with the switching on thereof, for example by
way of a user-side action. Said program sequence plan then
initially has the charging process state "Initialization". If a
fault arises, a change is made to the charging process state "Not
ready to charge". The fault may be based on, for example,
incomplete initialization, another internal system fault arisen in
the LEM or an external system fault communicated to the LEM, for
example a fault of the charging unit. If no fault arises, the
charging process state "Initialization" is considered to be
terminated. To this end, communication exchange with the charging
control system of the charging unit, which has confirmed or
prescribed the charging process state "Initialization", may also be
necessary.
After fault-free termination of the charging process state
"Initialization", the charging process state "Ready to charge"
follows in the program sequence plan. If a fault arises, which may
be internal as well as external in nature, a change is made to the
charging process state "Not ready to charge". As soon as the
readiness to charge is considered to be present there, possibly
after communication exchange with the charging control system, the
assumption of the charging process state "Ready to charge" results
again. If no fault arises and if the charging process state "Ready
to charge" is confirmed through communication exchange possibly by
the charging control system, which stipulates establishment of a
connection between an electric vehicle and a charging plug of the
charging unit, the next charging process state "Initialization of
charging interface" is assumed in the program sequence plan.
In the charging process state "Initialization of charging
interface", a selection of a predetermined charging system and of
charging parameters of the electric vehicle is transmitted from the
charging control system through communication exchange to the LEM.
If in the meantime the charging plug should be disconnected from
the electric vehicle, a change is made back to the previous
charging process state "Ready to charge". If otherwise a fault
should be identified, a transition is made to the charging process
state "Fault in charging process". If, however, no fault arises and
if the charging control system demands through communication
exchange an insulation measurement of the power electronics system,
the charging process state "Insulation measurement" results.
Otherwise, a change can be made to the charging process state "End
charging process" from the charging process state "Initialization
of charging interface" when the charging process is ended
prematurely, for example through interruption by the user at the
charging station.
With changing to the charging process state "Insulation
measurement", in the LEM an insulation measurement of the power
electronics system, and depending on the charging standard also an
insulation measurement of the charging cable, is demanded and the
result of this insulation measurement is awaited. If a fault arises
during the insulation measurement, a change is made to the charging
process state "Fault in charging process". If no fault arises and
the LEM sends a positive result, the next charging process state
"Precharging" follows, provided that this is also demanded by the
charging control system. Otherwise, a change can also be made to
the charging process state "End charging process" from the charging
process state "Insulation measurement" when the charging process is
ended prematurely.
In the charging process state "Precharging", a charging cable, the
power electronics system and possibly capacitances located on the
electric vehicle are precharged. If a fault arises, a change is
made to the charging process state "Fault in charging process".
However, if the precharging is carried out and the charging
parameters prescribed by the electric vehicle are confirmed by the
LEM, for example by adjusting a charging voltage, the next charging
process state "Charging" follows as long as the start thereof is
also demanded by the charging control system. Otherwise, a change
can also be made to the charging process state "End charging
process" from the charging process state "Precharging" when the
charging process is ended prematurely.
In the charging process state "Charging", a battery of the electric
vehicle is charged by way of a charging power according to the
charging system selection. The charging parameters of the electric
vehicle are constantly exchanged through communication exchange
between the electric vehicle, the charging control system and the
LEM. If a fault arises, a change is made to the charging process
state "Fault in charging process". However, if no fault arises, the
battery is charged up to full charge and, when the charging control
system demands the end of the charging process, a change is made to
the charging process state "End charging process", or a change is
made thereto anyway when the charging process is ended
prematurely.
In the charging process state "End charging process", an absence of
current and voltage is established at an output of the power
electronics system by the LEM and all DC voltage contactors are
opened. If a fault arises, a change is made to the charging process
state "Fault in charging process". If no fault arises and if the
absence of current and voltage is confirmed by the LEM and if the
DC voltage contactors are open, a change is made to the charging
process state "Charging process terminated".
The charging process state "Charging process terminated" is an
additional safety state in which the absence of current and voltage
and the opening of the DC voltage contactors is intended to be
confirmed again in order that a charging plug ultimately connected
to the LEM is definitely disconnected upon removal from the
electric vehicle. In this charging to process state, it is possible
to identify sticking or fusing of the contactors of the vehicle. To
this end, a voltage measurement is carried out upstream of the open
contactors in the direction of the charging column and the result
is transmitted to the electric vehicle by means of the charging
control system. If a fault arises, a change is made to the charging
process state "Fault in charging process". If no fault arises and
if the absence of current and voltage has been established, a
change is made to the charging process state "Ready to charge" as
soon as this has been demanded by the charging control system.
The charging process state "Fault in charging process" is reached
when a fault from the respective charging process states
"Initialization of charging interface", "Insulation measurement",
"Precharging", "Charging", "End charging process" and "Charging
process terminated" arises. If the fault can be eliminated and is
no longer present or the electric vehicle is no longer connected to
the charging unit, a change is made to the charging process state
"Ready to charge". However, if the fault cannot be eliminated, a
change is made to the charging process state "Not ready to
charge".
Finally, a change can be made to the charging process state "Ready
to charge" from the charging process state "Not ready to charge"
only when the readiness to charge has been re-established, for
example, through elimination of the fault.
In one embodiment of the method according to aspects of the
invention, a rapid charging process is carried out, the high
charging power of which is provided either by way of a high
direct-current voltage and/or a high direct-current.
A system for charging sequence control of a power electronics
system is also claimed, which system has the power electronics
system, a control device for the power electronics system and a
charging unit, which comprises a charging control system, and
wherein the system is configured, in order to charge a battery that
is to be connected to the charging unit, for example of an electric
vehicle, to carry out an embodiment of the method according to
aspects of the invention. A plurality of systems according to
aspects of the invention can form what is known as a charging park.
It is advantageous to divide the system according to aspects of the
invention into individual components, which are possibly arranged
physically distributed, since as a result a narrow charging column
with only a low visual obstruction in traffic is possible for
example as charging unit.
In one refinement of the system according to aspects of the
invention, the system additionally comprises a power electronics
control device. The power electronics control device and the power
electronics system can form a separate module, referred to as LEM
by a person skilled in the art, within a charging park and can be
arranged at a distance from the charging column that is to be
operated by the user.
In another refinement of the system according to aspects of the
invention, the system additionally comprises a ChargeBox
controller. The ChargeBox controller controls amongst other things
the power electronics system within a ChargeBox. In the case of the
ChargeBox, the charging column can also be placed up to 100 m away
and thus be brought toward the parking vehicles.
The system is designed together with the program sequence plan
according to aspects of the invention to ensure compatibility with
charging standards known to a person skilled in the art, such as
ChaDeMo, GB/T or CCS, for example.
BRIEF DESCRIPTION OF THE DRAWING
Further advantages and configurations of the invention emerge from
the description and from the appended drawing.
The FIGURE shows a program sequence plan corresponding to one
embodiment of the method according to aspects of the invention.
It is self-evident that the features mentioned above and the
features yet to be discussed below may be used not only in the
respectively specified combination but also in other combinations
or individually without departing from the scope of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
The FIGURE shows a program sequence plan 100 corresponding to one
embodiment of the method according to aspects of the invention. A
power electronics control device is selected as a control device of
a power electronics system, said control device communicating with
a charging control system. However, the same program sequence would
also be conceivable with a ChargeBox controller. Furthermore, in
the embodiment of the method according to aspects of the invention
shown, the charging control system can communicate with a charging
plug control device, which controls a charging plug, which is
located at the end of a charging cable connected to a charging unit
and is plugged into a corresponding charging socket on the electric
vehicle during a charging process of a battery comprised by an
electric vehicle. The power electronics system and the power
electronics control device are arranged in a power electronics
module, abbreviated to LEM. The program sequence plan 100 begins in
a switched-off state 110 of the LEM and, with switch-on 111, which
is triggered, for example, by a specific action of a user, such as,
for example, by plugging the charging plug into a charging socket
of an electric vehicle to be charged or by removing the charging
plug from the charging column or by touching a charging column
display, transitions to a charging process state "Initialization"
10, in which initialization 11 takes place. If a fault arises,
which may be based, for example, on incomplete initialization,
another internal system fault arisen in the LEM or an external
system fault communicated to the LEM, a change 108 is made to a
charging process state "Not ready to charge" 8. If no fault arises,
the charging process state "Initialization" 10 is considered to be
terminated. To this end, a communication exchange with the charging
control system of the charging unit, which has confirmed or
demanded the charging process state "Initialization" 10, may also
be necessary. After fault-free termination of the charging process
state "Initialization" 10, a charging process state "Ready to
charge" 1 follows in the program sequence plan. If a fault arises
in this charging process state, which may be internal as well as
external in nature, a change 18 is made to the charging process
state "Not ready to charge" 8. As soon as a readiness to charge 88
is considered to be present there, possibly after communication
exchange with the charging control system, a change 81 is made
again to the charging process state "Ready to charge" 1. If no
fault arises and if the charging process state "Ready to charge" 1
is confirmed through communication exchange possibly by the
charging control system, which stipulates establishment of a
connection between an electric vehicle and a charging plug of the
charging unit, a change 12 is made to a charging process state
"Initialization of charging interface" 2 in the program sequence
plan. In the charging process state "Initialization of charging
interface" 2, a selection from predetermined options of a charging
system and of charging parameters of the electric vehicle is
transmitted from the charging control system through communication
exchange 22 to the LEM. If in the meantime the charging plug should
be disconnected from the electric vehicle, a change 21 is made back
to the previous charging process state "Ready to charge" 1. If
otherwise a fault should be identified, a change 29 is made to the
charging process state "Fault in charging process" 9. If, however,
no fault arises and if the charging control system demands,
possibly prompted by the electric vehicle, through communication
exchange an insulation measurement 33 of the power electronics
system, a change 23 to a charging process state "Insulation
measurement" 3 results. Otherwise, a change 26 can be made to a
charging process state "End charging process" 6 from the charging
process state "Initialization of charging interface" 2 when the
charging process is ended prematurely, for example through
interruption by the user at the charging station. If a fault arises
during the insulation measurement 33, a change 39 is made to a
charging process state "Fault in charging process" 9. If no fault
arises and the LEM sends a positive result, a change 34 is made to
a charging process state "Precharging" 4, provided that this is
also demanded by the charging control system through communication
exchange with the LEM, wherein it may also be that this has been
demanded previously by a control device of the electric vehicle
during charging control. Otherwise, a change 36 is made from the
charging process state "Insulation measurement" 3 to the charging
process state "End charging process" 6 when the charging process is
ended prematurely. In the charging process state "Precharging" 4,
possibly a charging cable and possibly capacitances located on the
electric vehicle and possibly the power electronics system are
precharged, wherein it may also be that this is performed by the
electric vehicle itself. If a fault arises, a change 49 is made to
the charging process state "Fault in charging process" 9. However,
if the precharging 44 is carried out and the charging parameters
prescribed by the electric vehicle are confirmed by the LEM, for
example by adjusting a charging voltage, a change 45 is made to a
charging process state "Charging" 5, provided that the start
thereof is also demanded by the charging control system through
communication exchange with the LEM, wherein it may also be in this
case that this has been demanded previously by a control device of
the electric vehicle during charging control. Otherwise, a change
46 can also be made to the charging process state "End charging
process" 6 from the charging process state "Precharging" 4 when the
charging process is ended prematurely. In a charging process state
"Charging" 5, the battery of the electric vehicle is charged by way
of a charging power corresponding to the charging system selection
and the charging parameters of the electric vehicle. The charging
parameters of the electric vehicle are constantly exchanged through
communication exchange 55 between the electric vehicle, charging
control system and LEM, in particular between the electric vehicle
and the charging control system and between the charging control
system and the LEM. If a fault arises, a change 59 is made to the
charging process state "Fault in charging process" 9. However, if
no fault arises, the battery is charged up to full charge and, when
the electric vehicle and/or the charging control system demands the
end of the charging process, a change 56 is made to a charging
process state "End charging process" 6, or a change is made thereto
anyway when the charging process is ended prematurely. In the
charging process state "End charging process" 6, an absence of
current and voltage at an output of the power electronics system is
established and the associated DC voltage contactors are opened as
an action 66 of the LEM. If a fault arises, a change 69 is made to
the charging process state "Fault in charging process" 9. If no
fault arises and if the absence of current and voltage is confirmed
by the LEM and if the DC voltage contactors are open, a change 67
is made to a charging process state "Charging process terminated"
7. The charging process state "Charging process terminated" 7 is an
additional safety state 77 in which the absence of current and
voltage and the opening of the DC voltage contactors is intended to
be confirmed again by the power electronics control device in order
that the charging plug ultimately connected to the LEM through
electrical feedthrough is definitely switched to current-free or
voltage-free upon removal from the electric vehicle. Furthermore,
in said charging process state, sticking of the contactors of the
electric vehicle can be checked. If a fault arises, a change 79 is
made to the charging process state "Fault in charging process" 9.
If no fault arises and if the absence of current and voltage has
been established, a change 71 is made to the charging process state
"Ready to charge" 1, which can be demanded by the charging control
system or takes place automatically. The charging process state
"Fault in charging process" 9 is reached when a fault from the
respective charging process states "Initialization of charging
interface" 2, "Insulation measurement" 3, "Precharging" 4,
"Charging" 5, "End charging process" 6 and "Charging process
terminated" 7 arises. If the fault is eliminated 99 or the fault is
no longer present or the fault has been caused by the electric
vehicle and the electric vehicle is no longer connected to the
charging unit, a change 91 is made to the charging process state
"Ready to charge" 1. However, if the fault cannot be eliminated, a
change 98 is made to the charging process state "Not ready to
charge" 8. Finally, a change 81 can be made to the charging process
state "Ready to charge" from the charging process state "Not ready
to charge" 8 only when the readiness to charge has been
re-established, for example, through elimination of the fault
88.
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